Séminaires : Séminaire d'Algèbre

In this talk, we will first recall the constructions of triangular extension and of source-sink extensio for skew-symmetrizable matrices and some invariants under these constructions. Secondly, we will recall the string diagrams introduced by Shen-Weng, which are very useful to describe many interesting skew-symmetrizable matrices closely related with Lie theory. Thirdly, we will sketch the proof of our main result: the skew-symmetrizable matrices from string diagrams are in the smallest class of skew-symmetrizable matrices containing the (1 times 1) zero matrix and closed under mutations and source-sink extensions. This result applies to the exchange matrices of cluster algebras from double Bruhat cells, unipotent cells, double Bott-Samelson cells among others. Finally, some immediate applications regarding reddening sequences and non-degenerate potentials for many quivers from Lie theory are given.